Precipitation Reactions

By: Melissa Calderon

Precipitation reaction is basically when two solutions are mixed together, the reactants, and create a solid product (precipitate). Precipitation often happens with double replacement reaction.

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Equation:

reactant+reactant--->product+product

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Example 1:

2KI+Pb(NO3)2)----> 2KNO3+ PbI

potassium iodide+lead nitrate--->potassium nitrate+lead iodide

Both reactants form colorless solutions, but when they're poured together the lead iodide, product, is a yellow solid.

Example 1:

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Example 2:

2 AgNO3 + K2CrO4 ---> Ag2CrO4+ 2 KNO3

Potassium chromate (yellow) +silver nitrate (colorless)---> silver chromate+ potassium nitrate

One of the solutions is yellow and the other one is colorless when they're mixed together product is a red-orange solid.

First

Second

Third

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Resources:

Griffin, . "Chemical Reactions." Rates of Chemical Reactions. Rockford Public Schools, Web. 4 Mar. 2010. <http://students.ed.uiuc.edu/ljgriffi/project/grifunit3/griffchemicalreactions.htm#Evidence_of_Chemical_Reactions>.

Beyond Books, Apex Learning Inc.. "Precipitation." Introduction to Chemistry Concepts. 30 July 2007. Web. 4 Mar. 2010. <http://www.beyondbooks.com/psc92/8d.asp>.

Nave, R. Precipitation Reactions. Department of Physics and Astronomy, Aug. 2000. Web. 4 Mar. 2010. <http://hyperphysics.phy-astr.gsu.edu/Hbase/chemical/precip.html>.

M, Brian. "Precipitation Reactions." Understanding Chemical Reactions. The Chemistry Hypermedia Project, 3 Mar. 2000. Web. 4 Mar. 2010. <http://www.files.chem.vt.edu/chem-ed/general/rexn-intro.html>.